public override void Visit(KeyExpr expr)
{
if (expr.Target == null)
{
_needsAsync = true;
}
}
private Expr ParseIndexExpr(Expr prev)
{
var openBracket = Match("[");
var next = GetToken();
Expr projectionFilter = null;
if (next.Kind == "STRING" && GetToken(1).Kind == "]")
{
Match("STRING");
Match("]");
projectionFilter = new KeyExpr(GetLocation(next), prev, next.Text);
}
else if (next.Kind == "..")
{
Match("..");
next = GetToken();
if (next.Kind == "]")
{
Match("]");
projectionFilter = new SliceExpr(GetLocation(openBracket), prev, null, null);
}
else
{
var upperBound = ParseExpr();
projectionFilter = new SliceExpr(GetLocation(openBracket), prev, null, upperBound);
}
}
else
{
var filter = ParseExpr();
next = GetToken();
if (next.Kind == "..")
{
Expr upperBound = null;
Match("..");
next = GetToken();
if (next.Kind != "]")
{
upperBound = ParseExpr();
}
Match("]");
projectionFilter = new SliceExpr(GetLocation(openBracket), prev, filter, upperBound);
}
else
{
Match("]");
projectionFilter = new IndexExpr(GetLocation(openBracket), prev, filter);
}
}
return(projectionFilter);
}
public override String ToQueryPlan()
{
return(KeyExpr.ToExpressionStringMinPrecedenceSafe());
}
public override void Visit(KeyExpr expr) => _needsAsyncByItself = expr.Target == null ? true : _needsAsyncByItself;
public virtual void Visit(KeyExpr expr)
{
}
private Expr ParseMapProjectionExpr(Expr prev)
{
var bracket = Match("{");
var projections = new List <Expr>();
while (true)
{
var token = GetToken();
if (token.Kind == "}")
{
Match("}");
break;
}
string id = null;
Expr projection;
if (token.Kind == "}")
{
Match("}");
break;
}
if (token.Kind == "...")
{
var ellipsis = Match("...");
var next = GetToken();
projection = new SpreadExpr(GetLocation(ellipsis), ParseExpr());
}
else if (token.Kind == "$")
{
var dollar = Match("$");
var dollarLocation = GetLocation(dollar);
id = Match("ID").Text;
projection = new KeyValuePairExpr(dollarLocation, id, new VariableExpr(dollarLocation, id));
}
else
{
var idToken = MatchAny(new [] { "STRING", "ID" });
var idLocation = GetLocation(idToken);
id = idToken.Text;
var curr = GetToken();
if (curr.Kind == ":")
{
Match(":");
projection = new KeyValuePairExpr(idLocation, id, ParseExpr());
}
else if (curr.Kind == "{")
{
// These are all equivalent:
// foo: foo | { a, b, c }
// foo | { a, b, c }
// foo { a, b, c }
MatchOptional("|");
var rhs = new ChainExpr(
new KeyExpr(idLocation, prev, id),
ParseExpr(),
ChainBehavior.ToMultipleIfArray);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else if (curr.Kind == "(")
{
// key(a: 123) => key: key(a:123)
var keyExpr = new KeyExpr(idLocation, prev, id);
var rhs = ParseChainRemainder(keyExpr);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else if (curr.Kind == "[?")
{
// x[? filter] => x: x[? filter]
var keyExpr = new KeyExpr(idLocation, prev, id);
var rhs = ParseChainRemainder(keyExpr);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else if (curr.Kind == "[")
{
// x[5] => x: x[5]
var keyExpr = new KeyExpr(idLocation, prev, id);
var rhs = ParseChainRemainder(keyExpr);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else if (curr.Kind == "|")
{
// These are all equivalent:
// foo: foo | { a, b, c }
// foo | { a, b, c }
// foo { a, b, c }
MatchOptional("|");
var rhs = new ChainExpr(
new KeyExpr(idLocation, prev, id),
ParseExpr(),
ChainBehavior.OneToOne);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else if (curr.Kind == "|<")
{
// This is another shorthand for filtring an array of objects. These are equivalent:
/// foo: foo |< { a, b, c }
/// foo |< { a, b, c}
Match("|<");
var rhs = new ChainExpr(
new KeyExpr(idLocation, prev, id),
ParseExpr(),
ChainBehavior.ToMultiple);
projection = new KeyValuePairExpr(idLocation, id, rhs);
}
else
{
projection = new KeyValuePairExpr(idLocation, id, new KeyExpr(idLocation, null, id));
}
}
projections.Add(projection);
var tok = MatchAny(new [] { ",", "}" });
if (tok.Kind == "}")
{
break;
}
}
return(new MapProjectionExpr(GetLocation(bracket), prev, projections));
}
